The present invention relates to a cartridge for a consumable ribbon.
The present invention also relates to a roller for winding a ribbon from one of its ends into such a cartridge.
The present invention also relates to a ribbon-consuming apparatus, such as a printer, in particular a ticket office printer.
The present invention further relates to a method for rotationally coupling such a roller with a spindle for supporting and driving this roller.
The ribbon in question may be an ink ribbon which the apparatus consumes as it prints documents by a thermal printing process.
Printers issuing in particular tickets, reservation documents and other tickets for people travelling by air or by other means of transport are called ticket office printers.
In this type of printer, the ink ribbon is relatively wide and the lines are printed along the width of the ribbon, and printing is carried out in successive lines in the direction of the width of the ribbon perpendicular to the direction of unwinding of the ribbon and of the document to be printed. However, the invention is in no way limited to this configuration.
Ribbon-consuming apparatuses generally contain two rotating spindles to support a roller for unwinding the new ribbon and a roller for taking up the used ribbon respectively. It is necessary to carry out a rotational coupling between the take-up roller and the corresponding spindle which is a motor spindle, so that the take-up roller is entrained in the direction in which the ribbon is pulled towards the roller.
In many cases, it is also necessary to carry out a rotational coupling between the unwinding roller and the corresponding spindle, for example in order that the spindle transmits to the roller a braking torque corresponding to a predetermined tension of the ribbon. The possibility may also be provided, after first using all or part of the length of the ribbon, of rewinding the ribbon onto the unwinding roller in order to use the ribbon again, which will provide a still acceptable quality of printing. In order to carry out such a rewinding process, the unwinding spindle must also be equipped with a rapid reverse motorization.
When a new ribbon is being inserted, operations are made easier if the ribbon is contained in a cartridge. It is also possible for the new ribbon and the two rollers to be positioned on a loader, made for example of cardboard, which gives the rollers and the ribbon the exact position allowing the whole to slide directly into the ribbon-consuming apparatus by simple translation of the whole parallel to the axes of the rollers.
However, even with these simplifying means, the operator must still carry out the rotational coupling between each roller and its spindle whilst holding the strip along a path which is sufficiently precise for a region of the ribbon located between the two rollers to be inserted between a printing head and a printing surface. Moreover, in order to carry out the two rotational couplings, it is often necessary to turn the rollers slightly in order to find the position in which locking is possible, and this slight rotation of the rollers can only be carried out in the direction of release of the region of the ribbon which has to be placed between the printing head and the printing surface, which complicates the engagement and creates unfavourable initial operating conditions.
The aim of the invention is to remedy these disadvantages and in particular to allow better engagement of the new ribbon, and to provide improved initial conditions for using the ribbon in the receiving apparatus.